Why in the following functions do char* and void* need the same object representation and alignment requirements?

The answers to the questions raised yesterday have raised new doubts for me.
There is such a sentence in the official C99 rationale document:

What exactly does “interchangeability” in C language refer to?

C11 6.2.5 P28:

why does negative std::numeric_limits::infinity() trip the fail bit in a stream on Linux but not on AIX

I’m observing differing behavior when porting to IBM Open XL C++ 17.1 (clang frontend) with this test:

Undefiend reference after compilation

Assume there are 3 source files:

Why doesn’t a common_type_t result in a common type?

Consider this code:

How to discard the designator of a void expression in C？

My question is as described in the title.
C11 has the following description of void expressions:

Some issues about composite types in C

C11 6.2.7 p3：

C++ the problem of creating unnamed class object

here is my class code

Are the following examples of implicit qualification conversion reasonable in C?

The question raised a few days ago was not stated clearly. Now, I will try to raise this question in the shortest possible language.
Just look at an example here directly, or just look at the key clips I intercepted directly:

Changing options fr different objects

ALL,